This invention relates to multi-row heat exchangers used in heating, ventilating and air conditioning systems. In particular, this invention relates to a particular type of multi-row heat exchanger and to how this type of multi-row heat exchanger is formed.
It has heretofore been known to take a plurality of tubes and lace them with heat exchange fins so as to produce a row of heat exchange elements. This lacing process often begins with first inserting the ends of the tubes through holes in a tube holding device before passing the tubes through holes in the heat exchange fins. The ends of the tubes are finally inserted through a second tube holding device. The thus laced tubes are next subjected to an expander process wherein an expansion element larger than the inner diameter of the tubes is forcibly moved through each tube. The tubes expand so as to secure the heat exchanger fins and the tube holding devices thereto.
The resulting row of heat exchange elements may be subjected to several bending operations so as to be transformed into a particular heat exchanger configuration for a heating, ventilating and air conditioning system. The bent row may also be joined to several other bent rows of heat exchange elements to form a multi-row heat exchanger. It has also been known to simultaneously bend a number of rows of heat exchange elements so as to form a particular heat exchanger configuration.
Regardless of whether the rows are bent separately or simultaneously, it is important that each of the bent rows be aligned with respect to each other in the ultimate multi-row heat exchanger. This usually means that the ends of the rows, typically defined by the tube holding devices at each end, must end up in alignment in the ultimate multi-row heat exchanger.
It is an object of this invention to provide a process for forming multi-row heat exchange elements wherein the risk of misalignment of the tube holding devices at each end of the multiple rows of fin coils is minimized.
It is another object of the invention to provide apparatus which allows multi-row heat exchange elements to be formed into a final heat exchanger configuration without risk of misalignment of the tube holding devices.